(This issue was previously discussed through private messages but not yet resolved. It was noticed that a solution would require some "work around"! It is now recorded into the BTS for traceability reasons.)

My diagnostic is that a "-call-pdg" option is needed to handle this properly. However, I would love to be proven wrong, as this would be an invasive and complicated change --- not to mention of amount of time and memory it might require at execution. Could someone point to me a document that explains how the slicing currently uses -calldeps to improve its results?